Three policemen were killed and 10 more injured when a security vehicle was targeted with a roadside bomb in northwest Pakistan on Saturday, officials said.
The bomb exploded near a police van in Tor Ghar district of Khyber-Pakhtunkhwa province, district administration chief Farid Khan said.
Three policemen were killed while the 10 injured were taken to a hospital in Batgram, the main town in the region, the officials said.
A group of over 30 policemen was travelling to a training centre in a convoy of three vehicles when the blast occurred.
No group claimed responsibility for the attack but such bombings are usually blamed on the Taliban.
The government declared the mountainous Tor Ghar (Black Mountain) area a new district of Khyber-Pakhtunkhwa province this year and a new police force is being trained to assume security responsibilities.
Tor Ghar had attracted the world's attention in May, days after the US military raid killed Osama bin Laden in a compound in Abbottabad.
Local media had quoted residents of Tor Ghar as saying that US helicopters had landed in the area to refuel.
Reports said the security agencies had detained several persons in the area for their alleged role in providing fuel to the US military.